1. Field of the Invention
The present invention pertains to high-speed electronic data signal processing for continuously monitoring one or more data streams and automatically detecting and selectively modifying particular data patterns to produce correction, enhancement, improvement, etc. in real time. More particularly, the present invention pertains to a method and apparatus for automatically adjusting image density selectively in detected image areas within a desired region of an image frame or page so as to vary or blend the adjusted density within the detected areas which approach or are located near regional boundaries. One or more data streams can be modified, for example, to selectively lighten very dense image areas along the leading edge of each imaged page in order to enhance the reliability of paper handling through a xerographic processor. The present invention improves paper stripping reliability when paper exits the fuser roll, while minimally degrading visual image quality.
2. Description of Related Art
The intelligent, selective and precise digital processing and modification of complex digital information signals (such as video image data, or other intelligible digital data streams) at very high speeds has typically required complex functional modules with extensive computational and/or interpretive capability.
A number of efforts have been made to improve or enhance processed images. U.S. Pat. No. 4,736,438 to Persoon et al discloses an image processing device for real time processing wherein a two-dimensional array of pixels is compared to a known image. The image processor can receive up to three data inputs each of which is four bits wide. U.S. Pat. No. 4,143,401 to Coviello discloses a system for generating line drawings of a scanned image wherein changes in a gray scale of an image are detected and used to create a line drawing on the image. U.S. Pat. No. 4,365,304 to Ruhman et al discloses a method and apparatus for on-line data enhancement wherein a histogram modification method is used to enhance an image.
However, a need exists for a simple and cost effective electronic functional module which can be adapted to one or more serial data bit streams from any source, representing, for example, "video", serialized image data, or other encoded visual or other signal information, to faithfully monitor the data for unique codes or patterns, and automatically modify, replace, decode or otherwise respond to any number, or arrangements, of input codes as required or desired for a particular application.